src/java.base/unix/classes/java/io/FileDescriptor.java

@@ -57,20 +57,26 @@
      * true, if file is opened for appending.
      */
     private boolean append;
 
     /**
+     * true, if file is opened with O_DIRECT flag;
+     */
+    private boolean direct;
+
+    /**
      * Constructs an (invalid) FileDescriptor
      * object.
      */
     public FileDescriptor() {
         fd = -1;
     }
 
     private FileDescriptor(int fd) {
         this.fd = fd;
         this.append = getAppend(fd);
+        this.direct = getDirect(fd);
     }
 
     /**
      * A handle to the standard input stream. Usually, this file
      * descriptor is not used directly, but rather via the input stream

@@ -163,10 +169,18 @@
 
                 public boolean getAppend(FileDescriptor obj) {
                     return obj.append;
                 }
 
+                public void setDirect(FileDescriptor obj, boolean direct) {
+                    obj.direct = direct;
+                }
+
+                public boolean getDirect(FileDescriptor obj) {
+                    return obj.direct;
+                }
+
                 public void setHandle(FileDescriptor obj, long handle) {
                     throw new UnsupportedOperationException();
                 }
 
                 public long getHandle(FileDescriptor obj) {

@@ -179,10 +193,15 @@
     /**
      * Returns true, if the file was opened for appending.
      */
     private static native boolean getAppend(int fd);
 
+    /**
+     * Returns true, if the file was opened with O_DIRECT flag.
+     */
+    private native boolean getDirect(int fd);
+
     /*
      * Package private methods to track referents.
      * If multiple streams point to the same FileDescriptor, we cycle
      * through the list of all referents and call close()
      */